[luckyleaf2]

Its best to wait until they sex(male/female) or alternating nodes.If i were you i would start training the plants now.Tieing down branches.You just topped the plants so the new branches can be bent and tied.Make sure you have good ventilation in that closet.Training your plants will save vertical space but they will bush up and get a little crowded so good ventilation/air movement is important.But from my experience with when to start flowering Ive tried flowering plants at different times in veg and for me letting them mature in veg will give you a healthier plant and much better yield.Now some sativas can be thrown into flower as early as 2 weeks in veg depending on strain.Some sativa strains have long flowering times up to 13 weeks.